From 99c6dc117d27d6259214812bd0b113aaf467f600 Mon Sep 17 00:00:00 2001 From: Lennert Buytenhek Date: Sun, 22 Jun 2008 22:45:04 +0200 Subject: [ARM] Feroceon: L2 cache support This patch adds support for the unified Feroceon L2 cache controller as found in e.g. the Marvell Kirkwood and Marvell Discovery Duo families of ARM SoCs. Note that: - Page table walks are outer uncacheable on Kirkwood and Discovery Duo, since the ARMv5 spec provides no way to indicate outer cacheability of page table walks (specifying it in TTBR[4:3] is an ARMv6+ feature). This requires adding L2 cache clean instructions to proc-feroceon.S (dcache_clean_area(), set_pte()) as well as to tlbflush.h ({flush,clean}_pmd_entry()). The latter case is handled by defining a new TLB type (TLB_FEROCEON) which is almost identical to the v4wbi one but provides a TLB_L2CLEAN_FR flag. - The Feroceon L2 cache controller supports L2 range (i.e. 'clean L2 range by MVA' and 'invalidate L2 range by MVA') operations, and this patch uses those range operations for all Linux outer cache operations, as they are faster than the regular per-line operations. L2 range operations are not interruptible on this hardware, which avoids potential livelock issues, but can be bad for interrupt latency, so there is a compile-time tunable (MAX_RANGE_SIZE) which allows you to select the maximum range size to operate on at once. (Valid range is between one cache line and one 4KiB page, and must be a multiple of the line size.) Signed-off-by: Lennert Buytenhek --- include/asm-arm/tlbflush.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'include/asm-arm/tlbflush.h') diff --git a/include/asm-arm/tlbflush.h b/include/asm-arm/tlbflush.h index 8c6bc1bb9d1a..909656c747ef 100644 --- a/include/asm-arm/tlbflush.h +++ b/include/asm-arm/tlbflush.h @@ -39,6 +39,7 @@ #define TLB_V6_D_ASID (1 << 17) #define TLB_V6_I_ASID (1 << 18) +#define TLB_L2CLEAN_FR (1 << 29) /* Feroceon */ #define TLB_DCLEAN (1 << 30) #define TLB_WB (1 << 31) @@ -51,6 +52,7 @@ * v4 - ARMv4 without write buffer * v4wb - ARMv4 with write buffer without I TLB flush entry instruction * v4wbi - ARMv4 with write buffer with I TLB flush entry instruction + * fr - Feroceon (v4wbi with non-outer-cacheable page table walks) * v6wbi - ARMv6 with write buffer with I TLB flush entry instruction */ #undef _TLB @@ -103,6 +105,23 @@ # define v4wbi_always_flags (-1UL) #endif +#define fr_tlb_flags (TLB_WB | TLB_DCLEAN | TLB_L2CLEAN_FR | \ + TLB_V4_I_FULL | TLB_V4_D_FULL | \ + TLB_V4_I_PAGE | TLB_V4_D_PAGE) + +#ifdef CONFIG_CPU_TLB_FEROCEON +# define fr_possible_flags fr_tlb_flags +# define fr_always_flags fr_tlb_flags +# ifdef _TLB +# define MULTI_TLB 1 +# else +# define _TLB v4wbi +# endif +#else +# define fr_possible_flags 0 +# define fr_always_flags (-1UL) +#endif + #define v4wb_tlb_flags (TLB_WB | TLB_DCLEAN | \ TLB_V4_I_FULL | TLB_V4_D_FULL | \ TLB_V4_D_PAGE) @@ -245,12 +264,14 @@ extern struct cpu_tlb_fns cpu_tlb; #define possible_tlb_flags (v3_possible_flags | \ v4_possible_flags | \ v4wbi_possible_flags | \ + fr_possible_flags | \ v4wb_possible_flags | \ v6wbi_possible_flags) #define always_tlb_flags (v3_always_flags & \ v4_always_flags & \ v4wbi_always_flags & \ + fr_always_flags & \ v4wb_always_flags & \ v6wbi_always_flags) @@ -417,6 +438,11 @@ static inline void flush_pmd_entry(pmd_t *pmd) if (tlb_flag(TLB_DCLEAN)) asm("mcr p15, 0, %0, c7, c10, 1 @ flush_pmd" : : "r" (pmd) : "cc"); + + if (tlb_flag(TLB_L2CLEAN_FR)) + asm("mcr p15, 1, %0, c15, c9, 1 @ L2 flush_pmd" + : : "r" (pmd) : "cc"); + if (tlb_flag(TLB_WB)) dsb(); } @@ -428,6 +454,10 @@ static inline void clean_pmd_entry(pmd_t *pmd) if (tlb_flag(TLB_DCLEAN)) asm("mcr p15, 0, %0, c7, c10, 1 @ flush_pmd" : : "r" (pmd) : "cc"); + + if (tlb_flag(TLB_L2CLEAN_FR)) + asm("mcr p15, 1, %0, c15, c9, 1 @ L2 flush_pmd" + : : "r" (pmd) : "cc"); } #undef tlb_flag -- cgit v1.2.2